Disconnected Rivers

Disconnected Rivers: Linking Rivers to Landscapes

ELLEN E. WOHL
Copyright Date: 2004
Published by: Yale University Press
Pages: 320
https://www.jstor.org/stable/j.ctt1njmjw
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  • Book Info
    Disconnected Rivers
    Book Description:

    This important and accessible book surveys the history and present condition of river systems across the United States, showing how human activities have impoverished our rivers and impaired the connections between river worlds and other ecosystems.Ellen Wohl begins by introducing the basic physical, chemical, and biological processes operating in rivers. She then addresses changes in rivers resulting from settlement and expansion, describes the growth of federal involvement in managing rivers, and examines the recent efforts to rehabilitate and conserve river ecosystems. In each chapter she focuses on a specific regional case study and describes what happens to a particular river organism-a bird, North America's largest salamander, the paddlefish, and the American alligator-when people interfere with natural processes.

    eISBN: 978-0-300-12746-1
    Subjects: General Science

Table of Contents

  1. Front Matter
    (pp. i-vi)
  2. Table of Contents
    (pp. vii-viii)
  3. Preface
    (pp. ix-xiv)
  4. Acknowledgments
    (pp. xv-xviii)
  5. Chapter 1 Why Should We Care About Rivers?
    (pp. 1-7)

    Rivers reflect a continent’s history. Where forces far beneath the Earth’s crust force up mountain ranges, rivers flow swift and cold down steep, boulder-strewn channels. Where the Earth is still, rivers meander broadly, depositing thick plains of sand, silt, and clay.

    They also reflect a people’s history. Where people clear the forests for agriculture, river valleys retain sediments, recording the transitional period when the soil washes down from the hillslopes, and rivers become broad and shallow. Where peoplemine precious metals from hills or build electronics factories, river valley sediments contain the toxic by-products of these activities. People build canals, roads,...

  6. Chapter 2 American Rivers
    (pp. 8-39)

    The rivers of the United States are as diverse as the country’s people. The rivers meander slowly across marshy plains hazy with heat and humidity. They rush down steep, rocky gorges fed by the melting ice of glaciers. They flow hidden beneath the ground in limestone caves, or they flow only after a thunderstorm has abruptly saturated the desert’s surface.

    Animals adjust themselves to this diversity. Silvery salmon swim relentlessly up clear, cold waters to lay their eggs among gravels eroded from the jagged Sawtooth Mountains of Idaho. Catfish with barbels sensitive to subtle movements in murky water wait beneath...

  7. Chapter 3 Conquering a New World: Pioneer Impacts
    (pp. 40-93)

    Humans reached North America at least twelve thousand years ago. The first people likely migrated south after crossing the Bering Strait region from northern Asia. They may have come as early as forty thousand years ago and moved southward along the coastal region or through the interior. What we are certain of is that by twelve thousand years ago people were living throughout the length and breadth of the Americas.¹

    These earliest human inhabitants were hunter-gatherers. They modified the physical and biological environments locally through practices such as setting wildfires or building fish weirs in rivers. Native American burning and...

  8. Chapter 4 Poisoning America: Commercial Impacts
    (pp. 94-175)

    Land with a population density low enough to be called a frontier disappeared from the continental United States during the 1890s. By that time, the frontier had already been closed for a century in parts of the eastern and midwestern United States. As the U.S. population continued to grow through reproduction and immigration, diverse regions of the country became increasingly densely populated. When combined with rapidly advancing material technology, this increasing population density was reflected in progressively larger scale, more intensive, more organized use of natural resources by commercial and governmental entities. Activities begun by pioneering individuals or communities often...

  9. Chapter 5 Institutional Conquest: Bureaucratic Impacts
    (pp. 176-221)

    A government must eventually respond to the demands of its citizens if it is to remain in power. In the United States, these demands have included some aspect of river control for two hundred years. The construction of local, discontinuous levees along the lower Mississippi River by landowners during the early 1700s, for example, led to so many conflicts of interest among landowners that Secretary of War John C. Calhoun recommended that the Army Corps of Engineers take control in 1819. In 1824 Congress passed the Rivers and Harbors Bill authorizing the removal of sandbars and wood along the Mississippi...

  10. Chapter 6 Trying to Do the Right Thing: Rehabilitation Impacts
    (pp. 222-255)

    More than six billion humans inhabited the Earth at the start of the twenty-first century. This single fact is the best indicator of our shortterm technological successes because it implies a tremendous ability to alter the planet in order to facilitate immediate human needs. In the past, various human societies were overwhelmed by environmental crises that they did not have the technology to overcome. The Salado culture of central Arizona abandoned agricultural fields rendered infertile by salinization associated with irrigation during the fourteenth century. The city-state of Mohenjo-daro was abandoned around four thousand years ago, apparently in response to a...

  11. Chapter 7 Thinking in Terms of Rivers
    (pp. 256-272)

    Rivers of the six American regions described earlier in this book share many of the same impacts, although to differing degrees. Each region also has impacts that are particularly widespread and intense in that region. The following regional summaries include broad generalizations, and each region holds at least one relatively unimpacted river.

    Rivers of the Northeast and East-Central region have the longest history of intensive European American land use in the United States. Widespread deforestation and cropping, as well as construction of small dams, commercial fishing, and industrialization and urbanization, have affected this region for more than two centuries. Flow...

  12. Notes
    (pp. 273-298)
  13. Index
    (pp. 299-301)